Evaluation of Mulching Performance in Increasing the Deep Percolation of Rainwater into the Soil

Using mulch is one of the ways which has been used so far to reduce the amount of evaporation. Accordingly, in this research, mulch effectiveness has been investigated in increasing the direct recharge of groundwater due to increased rainwater percolation. For this purpose, eight rainstorms with different durations and depths were tested. The depth of percolation of these rainfalls in the soil of 4 lysimeters with similar condition and different mulches, including gravel mulch, sand mulch, mixed 50% sand and 50% gravel mulch were tested as well as in non-covered soils. During the two months of the experiment, 192 data were collected for each soil moisture and rainfall percolation depth. The results showed that the mean rainwater percolation depth by gravel mulch, sand mulch and mixed sand and gravel mulch was respectively 19.52, 2.45 and 16.60 percent increased comparing to the soil without mulch. It was found that mulching can increases rainwater penetration as one of the main sources of groundwater recharge, by reducing the amount of rain water evaporation and therefore the results of this research can be used to aquifer restoration.